Algae contain high amounts of arsenic in the form of arsenosugars. The metabolism and toxicology of these arsenic species are not yet fully understood. Three sets of experiments have been conducted in which the alga Laminaria was ingested by 2 to 5 healthy volunteers. Total arsenic concentrations in urine and in blood, packed blood cells and serum have been determined using ICP-MS and HGAFS, respectively. Neutron activation analysis was used for the determination of the total arsenic content in algae samples. Speciation analysis of urine and serum samples has been carried out using HPLC-ICP-MS. HPLC-ES-MS/MS has been used for structural confirmation. The stability of the arsenosugars in simulated gastric fluid was studied for both boiled and unboiled seaweed. A maximum level of arsenic in urine appears within 15 to 25 h after ingestion. Total arsenic and speciation analysis revealed no marked increase in arsenic blood, serum and packed cells levels up to 7 h after ingestion. Dimethylarsinic acid (DMA), methylarsonic acid (MA) and dimethylarsinoylethanol (DMAE) have been positively identified in urine sampled after algae intake. Another 5 species remain unknown. In simulated gastric fluid incubated with algae, the larger share of the arsenosugars degrade within a short time span into a compound with a mass of 254 Da.

Neutron Activation Analysis (NAA) was used to investigate trace element patterns in serum, packed cells, and dialysate of CAPD patients. The concentrations of the elements Cs, Cu, Fe, and Mn in serum and packed cells appeared to be maintained within the normal range, while the levels of the non-essential element Br in both serum and packed cells were subnormal. The serum Cr values were extremely high (20 to 50 times higher than the normal serum level). The amount of Cr absorbed from the dialysate was calculated to be ten times higher than the daily dietary uptake. The Co concentrations were normal in packed cells but were significantly increased in serum. The Rb content in packed cells was slightly lower than normal, while the serum value was normal. Se was maintained within the normal range in packed cells, but the serum concentration was slightly lower than normal. The concentrations of Zn were low in serum and appeared to be higher than normal in packed cells. In conclusion, this analysis of the trace element status of CAPD patients reveals two major abnormalities. There is an apparent loss of Br from the blood towards the dialysate and on the other hand, a dramatic accumulation of Cr into the blood as a result of the very high Cr content in the dialysate.

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Arsenic (As) bound to serum proteins in patients on continuous ambulatory peritoneal dialysis (CAPD) was studied. A prior experiment by ultrafiltration showed that 5.57% of total As was bound to serum proteins for 14 CAPD patients. Further identification of the As species and protein molecules in serum of three CAPD patients with high As concentrations was carried out by combining the separation methods of size-exclusion, anion-exchange, and affinity fast-protein liquid chromatography, detected by hydride generation atomic absorption spectrometry. The results indicated that only inorganic As species are bound to serum proteins. Transferrin is the main carrier. The concentrations of As bound to proteins in serum for the three patients were 0.44 ± 0.12, 0.19 ± 0.09, and 0.59 ± 0.09 μg/L (n = 3), respectively.

A miniaturized HPLC column (Supelcosil LC-SAX 1, e.g., by the complexing ability of one of their oxidation states,12-14 by hydride generation (HG) or cold-trapping,14-19 2 cm×4.6 mm id) was coupled to HGAAS for the speciation of inorganic SbIII and SbV species in spiked water samples. The or by chromatography,20-22 the methods are essentially based on the determination of total Sb, evaluating SbV by difference. baseline separation of these two Sb species was achieved by using aqueous 50 mmol l−1 tartrate solution at pH 5.5 asHardly any analytical procedure can simultaneously separate and measure SbIII and SbV in one step. eluent. The retention times were 0.5 and 2.8 min for SbV and SbIII, respectively. The hydrides were generated with 3%Recently, Smichowski et al.23 proposed a method of highperformance liquid chromatography (HPLC) coupled to NaBH 4 and 1.8 mol l−1 HCl solutions. The absorbance was linearly related to the concentration of SbV species in the range hydride generation atomic absorption spectrometry (HGAAS) and inductively coupled plasma mass spectrometry (ICP-MS) 2.5-100 mg l−1 (r=0.9996) and of SbIII species in the range 5.0-100 mg l−1 (r=0.9990) with detection limits of 1.0 and for the speciation of SbIII and SbV species in natural water samples. This method offers the advantage of on-line separation 2.0 mg l−1, for SbV and SbIII, respectively. The precision, evaluated by using the relative standard deviation (RSD), was and determination of inorganic SbIII and SbV-species. They used, however, a needlessly long HPLC column (25 cm), 3.3% and 1.5% (n=10) for SbV and SbIII at concentrations of 50 mg l−1, and 4.1% and 3.9% (n=10) at concentrations of leading to a very long retention time of the last-eluted Sb species with serious broadening of the chromatographic peak. 10 mg l−1, respectively. The detection limits achieved in the present work are acceptable for screening samples with respect Moreover, a longer column is more expensive. The purpose of the present study is to explore the possibility of using a to the EU drinking and surface water limits (10 mg l−1), but are not sufficiently sensitive to measure real levels in natural miniaturized HPLC column coupled to HGAAS for the speciation of inorganic SbIII and SbV species in natural water waters. The accuracy of the method was evaluated by the analysis of Sb species in several spiked water samples, as there samples, in order to improve the detection limits of the Sb-species, to save analytical time and to make the method is yet no certified reference material available. more economical.